A TCM tune will help allot.
i agree, raising shift points will help keep on top of the charger during shifts and less a chance of "falling off" the charger. if after that you still dont like how it drives then a tighter AR would be the next step. keeping the biggest AR on there and still being drivable, to your preference, is what you want. that way you can keeps your egts and drive pressure down by still using the larger housing.
i know people running s400 t6 1.10 housings with 96mm turbine on street strucks and they dont lite to bad at all. he has the flow and fuel to get it lite though, 2 1/4" up pipes/ped/man., duel fuelers, injectors, ect. and a loose converter as well, 2500 rpm + stall. a stock truck could never spool a charger that size on the street though.
also have to keep in mind whether or not your ever going to be pulling a trailer.